Trim needless comments and fix the picker width

Remove comments that only restate the code, keeping the section banners
and the notes that carry a reason, a measured fact or an external
contract.

ButtonOptions.width claimed to be a fixed width but only set minWidth,
so the Graph and Texture pickers grew with the name they showed. It is
now what it promises, with a separate minWidth for the buttons that have
two forms. Narrow buttons shrink their padding, otherwise a 24px icon
button had 8px left for its glyph and truncate dropped it entirely.

__gm.labelsDropped() guards that class: the overflow guard only saw text
that was too wide, never a label truncated to nothing.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/editor/actions.ts

@@ -32,18 +32,13 @@ export function removeObjects(state: EditorState, sceneId: string, objectIds: re
   return state.execute(new RemoveSceneObjectsCommand(sceneId, objectIds));
 }
 
-/**
- * Asks before deleting an asset, spelling out what goes with it. Both ways of deleting (the
- * asset list's context menu and the Delete key) go through here, so the warning cannot differ
- * depending on how the user triggered it.
- */
+/** Asks before deleting an asset, spelling out what goes with it. */
 export function confirmDeleteAsset(state: EditorState, assetId: string): void {
   const asset = findAsset(state.project, assetId);
   if (!asset) return;
   const usages = findUsages(state.project, assetId).length;
-  // A texture is never placed – it is worn through a property – so counting placed instances
-  // would report "unused" for a picture a dozen sprites are showing. Its frames count as the
-  // texture itself: a sprite wearing one of them loses its picture just the same.
+  // A texture is never placed but worn through a property, so counting placed instances would
+  // report "unused". Its frames count as the texture itself.
   const ids = asset.type === 'texture' ? textureRefIds(asset) : assetId;
   const references = findPropertyUsages(state.project, ids).length;
   const detail =